The present invention relates to a rotary direction detecting sensor for use in an automobile, and more particularly, to a detector for detecting the direction of rotation of a steering wheel.
Recently, in an automobile, a switch for blinkig a turn indicator lamp has been mounted on a place other than a steering column, such as an instrument panel. In such a case, when the steering wheel is returned to its neutral position after the completion of a turning movement of the automobile, it is required to detect the direction of rotation of the steering wheel so as to turn off the turn indicator lamp in accordance with the direction of the rotation. For this purpose, various rotary direction detecting sensors have been proposed previously, such as U.S. Pat. Nos. 4,323,877 and 4,571,469. However, in the structure of the previous rotary direction detecting sensors, a large annular space in a radial direction around a steering shaft is needed since movable contacts are provided all around the periphery of the shaft, so that the sensor becomes bulky in size.